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arXiv · 1811.02258

Specific heat of 2D interacting Majorana fermions from holography

Paolo Maraner·Jiannis K. Pachos·Giandomenico Palumbo
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Abstract

Majorana fermions are a fascinating medium for discovering new phases of matter. However, the standard analytical tools are very limited in probing the non-perturbative aspects of interacting Majoranas in more than one dimensions. Here, we employ the holographic correspondence to determine the specific heat of a two-dimensional interacting gapless Majorana system. To perform our analysis we first describe the interactions in terms of a pseudo-scalar torsion field. We then allow fluctuations in the background curvature thus identifying our model with a $(2+1)$-dimensional Anti-de Sitter (AdS) geometry with torsion. By employing the AdS/CFT correspondence, we show that the interacting model is dual to a $(1+1)$-dimensional conformal field theory (CFT) with central charge that depends on the interaction coupling. This non-perturbative result enables us to determine the effect interactions have in the specific heat of the system at the zero temperature limit.

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Paolo Maraner, Jiannis K. Pachos, Giandomenico Palumbo. 2018-11-06. Specific heat of 2D interacting Majorana fermions from holography. https://doi.org/10.1038/s41598-019-53771-5

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